Railway signaling



Oct. 7, 1924. x

L. v. LEWIS RAILWAY SIGNALING Filed July 25 1917 WITNESSES 5 INVENTOR.

BY Q I AA; ATTORNEY.

Patented Got. 7, 1924.

UNITED STATES PATENT OFFICE.

LLOYD V. LEWIS, OF EDGEWOO D BOROUGH, PENNSYLVANIA, ASSIGNO R TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A COBIOBLA'IION OF PENNSYLVANIA.

RAILWAY SIGNALING.

"Application filed. July 25, 1917. Serial No. 182,652.

To all whom it may concern:

Be it known that I, LLoYn V. LEjwrs, a citizen of the United States, residing at Edgewood Borough, in the county of Alle- Referring to the drawing the referencecharacter 2 designates the track rails of a railway which rails are divided by means of insulated joints 3 into a :lurality of successive block sections A- B-C, C-D, etc. Each-track section is provided with a track circuit comprising the track rails themselves, means for supplying alternating signaling current to the rails, and a relayH 7 having a winding receiving energyfrom the rails. For each track section I provide two sources of alternating current, differing 1n frequency, one or the other of which sources is connected with the rails of the section according to traffic conditions in advance of the section. Each relay is'selectively responsive to the frequency of the current by which it is energized; that is, it responds to one frequency by closing one contact or set of contacts, and to the other frequency by closing another Contact or set of contacts. As here shown, these relays are of a centrifugal type, but I do not wish to limit myself to relays of any particular character.

Each relay H comprises an induction motor M having a rotor 6 and two stator windings 4E and 5. The winding 4:, which I will term the track winding, is connected directly to the track rails of the section, while the other winding 5, which I will term the line winding, is supplied with alternating current by means which I will explain hereinafter. Theinduction motor operates a centrifuge K which in turn aot s he con a t f the re ay. This centrifuge is of a usual type comprising arms carrying weights 22 which tend to fly outwarrlly'when the centrifuge'is'rotated. The pp r arms25 are pivotally onne ted to a yoke 26 which is fixed to a shaft 27 connected with the rotor of motor M. The lower arms 23 are pivotally connected'to a yoke 24: which slides freely on th'e'shaft and to'which is also connected a lever 29 pivotally mounted at point '29 and provided: on its opposite end with a weight 29". When the centrifuge is at rest, lever 29 rests with its weight 29 against the lower arm of a fixed stop 30 (see relay for section CD). When the motor Mis supplied with current of a certain frequency, which I will herein assume to be cycles, the force exerted on lever 29.by the centrifuge K is sufficient to raise this lever 29'to an intermediate position wherein it engages with a 'st'em' 31 mounted for vertical movement in stop 30 and carrying a weight 31 at its upper end, but at this speed the action on lever 29 is not suiiicient to cause the lever to raise this weight (see relay for section B-C). lVhen motor M-issupplied with current of a higher frequency, which I will herein assume to be 90 cycles, "the force exerted on lever 29 by the centrifuge is sufficient to cause this lever to raise the weight 31,,so that the lever then rises until arrested by the upper arm of stop 30' (see relay for section A-B)'. It will be seen,

therefore, that lever 29 occupies any oneof three positions, depending on whether the motor -M is deenergized or is energized by act with their fixed contacts in the same manner as finger"'7. 1 a

Two 'sources of alternating signaling cur-- rentar'e provided for. each tracksection, these sources being in the case here shown, 60 cycles and cycles, respectively, corresponding-to'the two frequencies for which th? r ay a e a ju ed; -o1rd.er*t0- sim- 1' plify the drawing I have omitted the sources of current and the transmission lines by which these currents are distributed to the several sections, and have illustrated only the parts of the circuits which pass through the apparatus actually shown in the drawing. The wires which are connected with one terminal of a source of current are marked or 90 -designating the frequency of such source, while the wires which are connected with the other terminal of the source are marked 0, it being understood that the latter terminals of the two sources are connected together.

The relay for each section controls the frequency of the current which is supplied to the track rails of the section in the rear, and also to the line winding 5 of the relay for such section in the rear. When any relay H is deenergized, that is, when its centrifuge is at rest (see relay for section CD), 60 cycle current is supplied to the track circuit of the section in the rear, the circuit being from the 60 cycle source through relay con tact 87, wire 11, one rail of the section in the rear, the track winding 4 of the relay for such section in the rear, the other rail, and wire 12 to the common return wire. At the same time, 60 cycle current is supplied to the line winding of the relay for the section in the rear, the circuit being from the 60 cycle source through relay contact 1413, wire 17, relay winding 5 to the common return wire. The relay for such section in the rear is then energized by 60 cycle current in both windings, so that contacts 79, 13-15, and 1820 are closed (see relay for section BC).

lVhen any relay is energized by 60 cycle current, it supplies 9O cycle current to the rails of the section in the rear, and also to the line winding 5 of the relay for such section in the rear. The track circuit for such section in the rear is then from the 90 cycle source through relay contact 97, thence as before. The circuit for the line winding 5 is from the 90 cycle source through relay con-. tact 1513, thence as before.

When any relay is energized by 90 cycle current, it supplies 9O cycle current to the track rails of the section in the rear, and also tion and proceed.

to the line winding of the relay for such section in the rear, these currents being supplied through relay contacts 107, and 1613.

For each sectign I provide a signal S which is adapted to indicate stop, cau- Each signal is controlled by the relay H for the same section in such manner that the signal indicates stop when the relay is de -energized, caution when the relay is energized by 60 cycle current, and proceed when the relay is energized by cycle current. As here shown, each signal comprises three electric lamps R, Y and G, indicating when illumi nated stop, caution and proceed respectively, and these lamps are provided with circuits controlled by contact finger 18 of the corresponding relay. As will be obvious from the drawing, lamp R is illuininated when contact 18-19 is closed; that is, when the relay is de-energized; lamp Y is illuminated when contact 1820 is closed, that is, when the relay is energized by 60 cycle current; and lamp G is illuminated when contact 18-21 is closed, that is, when the relay is energized by 90 cycle current. In order to simplify the drawing I have omitted the source of current for the lamps of signal S and have shown only the portions of the circuits of these lamps which pass through the apparatus actually illustrated. It is understood that the wire marked B is connected with one terminal ofa suitable source of current and that the wire marked 0 is connected with the other terminal of the same source. It is further understood that lamps G, Y and R of each signal are provided with colored lenses or colored screens, so that the light emanating from these lamps are differently colored; for example, the light from lamp R nay be red, the light from Y may be yellow, andthe light from lamp Gr may be green.

As shown in the drawing, section C-D is occupied by a car or train T, so that relay H for this section is de-energized and the signal S for this section indicates stop. By virtue of the positions of contacts 7 and 13 of the relay for section CD, both windings of the relay for section BC are supplied with 60 cycle current, so that the contacts of this latter relay occupy their intermediate positions. Signal S for section BC consequently indicates caution, and both windings of the relay for section A-B are supplied with 90 cycle current. The contacts for this latter relay are therefore in their upper positions so that signal S for section A-B indicates proceed. Both windings of the relay for the section in the rear of section A-B are, of course, energized with 9O cycle current, so that the signal (not shown) for such latter section likewise indicates proceed. As the train T passes out of section CD into the next section in ad Vance, relay H for this section will become energized by 60 cycle current so that signal S for this section will indicate caution. The relay for section BC will then become energize-d by 90 cycle current so that the signal for this latter section will change to proceed. It is thought that the operation of the system will be obvious without further'explanation.

One important feature of the present invention is that the relay operating mechanism passes consecutively from the caution to the proceed position and Viceversa without passing through the stop position, so that no special means are necessary to prevent momentary closure of the stop contact, and so to prevent blinking of the stop lamp, during such change.

lVhen the relay is used to control a semaphore signal, the contacts may be so adjusted that when the relay is changing from the caution to the proceed position, or vice-versa, contact 20 will not open until contact 21 has closed, or vice-versa, thus avoiding momentary opening of the holding clear circuit and so avoiding the necessity for a slow-acting intermediate relay or a slow-acting holding magnet in the signal.

Although I have herein shown and described only one form of signaling system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is: v

1. A railway signaling system comprising a plurality of track sections, a relay for each section having a track winding receiving energy from the rails of the section and a line winding, each relay responding selectively to alternating currents of two frequencies in its windings, means controlled by the relay of each section for supplying current of one of said frequencies or the other to the-rails of the section in the rear, means also controlled by the relay of each section for supplying to the line winding of the relay for the section in the rear alternating current of the same frequency as is supplied to the rails of said section in the rear, and signals controlled by said relays.

2. A railway signaling system comprising a plurality of track sections, a relay for each section having a track winding receiving energy from the rails of the section and a line winding, each relay responding selectively to alternating currents of two frequencies in its windings, means controlled by the relay of each section for supplying current of one of said frequencies to the rails of the section in the rear when the relay is de-energized and for supplying current of the other frequency to said rails when the relay is energized by current of either of said frequencies, means also con trolled by the relay of each section for supplying to the line winding of the relay for the section in the rear alternating current of the same frequency as is supplied to the rails of said section in the rear, and signals controlled by said relays.

3. A railway signaling system comprising a plurality of track sections, a relay for each section comprising a motor having a track winding receivlng energy from the rails of the section and a line winding, said 7 one of said frequencies or the other to the 1 rails of the section in the rear, means also controlled by the relay of each section for supplying to the line winding of the relay for the section in the rear alternating current of the same frequency as is supplied to the rails of said section in the rear, and signals controlled" by said relays. v

4:. A railway signaling system comprising a plurality of track sections, a relay for each section having a track winding receiving energy from the rails of the section and a line winding, each relay responding selectively to alternating currents of two characteristics in its windings, means controlled by the relay of each section for supplying current of one of said characteristics or the other'to the rails of the section in the rear, means also controlled by the relay of each section for supplying to the line winding of the relay for the section in the rear alternating currentof the same characteristic as is supplied to the rails of said-section in the rear, and signals controlled by said relays.

5. A railway signaling system comprising a plurality of track sections, a relay for each section having, a track winding receiving energy from the rails of the section and a line winding, each relay responding selectively to alternating currents of two charac teristics in its windings, means controlled by the relay of each section for" supplying either of said characteristics, means also controlled by the relay of each section for supplying to the line winding lot the relay for the section in the rear alternating current of the same characteristic as is sup-' plied to the rails of said section in the rear, and signals controlled by said relays.

In testimony whereof I affix my signature in presence of two witnesses.

LLOYD v. LEWIS.

lVitnesses:

A. HERMAN VVEGNER, E. P. CRUM. 

